The term saponification is the name given to the chemical reaction that
occurs when a vegetable oil or animal fat is mixed with a strong alkali. The
products of the reaction are two: soap and glycerin. Water is also present,
but it does not enter into the chemical reaction. The water is only a
vehicle for the alkali, which is otherwise a dry powder.
The name saponification literally
means "soap making". The root word, "sapo", is Latin for soap. The Italian
word for soap is sapone. Soap making as an art has its origins in ancient
Babylon around 2500 - 2800 BC.
The oils used in modern
handmade soap are carefully chosen by the soap maker for the character they
impart to the final soap. Coconut oil creates lots of glycerin, makes big
bubbly lather, and is very stable. Olive oil has natural antioxidants and
its soap makes a creamier lather. Tallow, or rendered beef fat, makes a
white, stately bar that is firm and creates abundant lather. Many other oils
can be used, each one for a specific reason. Your soap maker will be glad to
tell you which oils are used to make her or his soap.
The alkali used in modern soap
is either potassium hydroxide, which is used to make soft soap or liquid
soap because of its greater solubility, or sodium hydroxide, which is used
to make bar soap. The common term for the alkali became simply "lye", which
curiously is not short for alkali, but originated in the Anglo-Saxon
language.
Soap made in cottages and on
farms in earlier American times became known as "lye soap". That term is now
pejorative and derogatory and denotes a harsh soap that would irritate your
skin. The old soap got a bad name because it had an excessive amount of
caustic. Weighing and measuring techniques were crude, and knowledge of soap
chemistry was elementary or non-existent.
The true fact is that modern
handcrafted soap, though necessarily made with lye to get true soap, has no
lye in the final product. It has all been reacted with the oils to form soap
and glycerin.
A curious fact about modern
soap is that most common soap found in the grocery store made in
mass-produced factories does have a small amount of excess alkali in it.
Also, it has had all of its naturally-occurring glycerin removed so it can
be sold as a separate commodity. Why? Greater profit. An important
difference between most commercial soap and our Real Handmade soap is that
the glycerin is left in Real Handmade Soap and thus it retains its natural
moisturizing property.
~~Richard Hamner, Green
Mountain Soap Company
